What is a SIM card used for? A SIM card, or a subscriber identity module/subscriber identification module, is a tiny memory card that contains unique information and is linked to a particular network ...

If you’ve bought an iPad with 4G/cellular capabilities (we discuss whether that’s a good idea in our 2015 iPad buying guide) or a new iPhone, you need to buy and install a SIM card. Here, we explain ...

Posts from this topic will be added to your daily email digest and your homepage feed. is a reviews editor who manages how-tos and various projects. She’s worked as an editor and writer (and ...

While most people manage quite well with a single SIM card, if you want better demarcation between your work and home life, or you want to make roaming with multiple SIM cards easier, then having the ...